Protein Domain : Antifreeze, type III IPR006013

Type	Family
Description	Marine teleosts from polar oceans can be protected from freezing in icy sea-water by serum antifreeze proteins (AFPs) or glycoproteins (AFGPs) [ ]: these function by binding to, and preventing the growth of, ice crystals within the fish. Despite functional similarity, the proteins are structurally diverse and include glycosylated and at least 3 non-glycosylated forms: the AFGP of notothenioids and cods are polymers of atripeptide repeat, Ala-Ala-Thr, with a disaccharide attached to the threonine residue; type I AFPs are Ala-rich, α-helical peptides found in flounder and sculpin; type II AFPs of sea-raven, smelt and herring are Cys-rich proteins; and type III AFPs, found in eelpouts, are rich in β-structure [ ]. As well as antifreeze proteins, this domain is also found in the C-terminal region of at least one sialic acid synthase (SAS). The function of this domain in SAS is not known, but it may be involved in sugar binding [].
Short Name	Antifreeze_III